[" An atom of an element "X" may be written as "_(4)^(9)X],[" (a) What does the figure "9" indicate? "]

An atom of an element X may be written as ._(4)^(9)X What does the figure 9 indicate ? (b) What does the figure 4 indicate ? (c) What is the number of protons in atom X ? (d) What is the number of neutrons in atom X ? (e) What is the number electron in atom X ? (f) How many electrons are there in the outermost shell of an atom of element X ? (g) Write the symbol of ion formed by an atom of element X.

Arrhenius equation may be written as

Arrhenius equation may be written as:

An atom of the element is represented as "_23^61X ? What is the number of protons in X ?

Atoms of the same element may have different _______.

Atoms of the same element may have different ________.

The atom of an element X has 7 electrons in its M shell. What is the atomic number of element X ?

Atoms of the same element may have different atomic mass .

The atomic number of an element X is 16. (b) What will be the valency of X ?